1. Field of the Invention
The present invention relates to an opening and closing damping apparatus for slowly opening and closing a rotation body.
2. Description of the Related Art
Conventionally, structure bodies having various opening and closing mechanisms are provided in the vehicle interior of a vehicle such as an automobile. The structure bodies include a retractable hook apparatus, a retractable assist grip apparatus, a retractable storage box, a cup holder, a glove box, a console box, etc.
As the opening and closing mechanisms, there is also a mechanism for together providing an opening and closing damping mechanism which has a shaft part for supporting a rotation member, a support body for rotatably supporting the shaft part and a spring for always energizing the rotation member in an opening direction or a closing direction, and further slowly opens and closes the rotation member against energization force of the spring.
As the opening and closing damping mechanism, a grease damper constructed so that there are provided a cylindrical support body and a columnar shaft body which is inserted into this support body and also is integrated with an opening and closing body and a grease passage and a grease retention are formed in the shaft body and grease with a predetermined viscosity is injected between the shaft body and an inner circumference of the support body and thereby the grease is retained in the grease passage and the grease retention and the opening and closing body is slowly rotated by the viscosity of this grease is disclosed in, for example, JP-A-10-54171.
In this art, it is constructed so as to prevent leakage of the grease without using sealing means such as an O ring by using the grease with the predetermined viscosity and retaining the grease in the grease retention, so that the number of parts can be reduced.
Also, a rotary damper constructed so that grease or oil is not used as a member for damping opening and closing of an opening and closing body integrally provided in a shaft body and the opening and closing body is slowly rotated by friction sliding between a support body and the shaft body is disclosed in JP-A-2002-193012.
In this art, grease or oil acting as the damping member is not required, so that that the number of parts can be reduced.
However, in the art disclosed in JP-A-10-54171, the support body for rotatably supporting the shaft body is required, so that there is a problem that assembly and manufacture of the support body become complicated and product cost increases. Further, since the shaft body is used as a component of the damper, applied material is limited in the case of use in a place in which rigidity is required, so that there is a problem that it is lacking in versatility.
In addition, since a sealing member such as an O ring is not used, a certain level of viscosity is required in grease in order to prevent leakage of the grease, so that limitation is imposed on a choice of grease, for example, grease with a low viscosity cannot be used.
On the other hand, in the art disclosed in JP-A-2002-193012, opening and closing damping attempts to be applied by friction sliding between members without using grease, so that a contact region between the members tends to wear with time and there is a problem in durability.